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We Did It! Portola Valley Field Day

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Revised: 20120711

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Chris Raanes W6CAR, Ray Rothrock WB5NVN, Steve Goldberg WQ6L & me.
Notable visitors ARRL SCV Section Manager Phil Steffora K6TT, and Brandon Bianchi NI6C—New SCV Section Manager (Starting July 1) pitched in; Councilman (ret) Steve Toben.

Notice that the perfect weather and abundant food forced us to work in obviously dire emergency conditions.

More seriously, this exercise exhibits intrinsic merit of a deep tradition for testing rapid deployment and evolving versatility. In fact, the ionosphere was not particularly kind this day, limiting the distance of confirmable HF (1.8-30 MHz) contacts and causing considerable re-strategizing. Ironically, this HF vulnerability to the “Maximum Usable Frequency” simultaneously highlighted the need and role of satellites; which have their own limitations, but do not depend on ionospheric bounce.

My previous field day may have been 40 years ago: and I had to ponder what my mentors might think of now portably tracking satellites while operating indefinitely from solar power. In the 60/70s we paid scant attention to the satellite fringe. Now, with cubesats reportedly available for $10K, the relevance and role of private satellites renders yet another dramatic communications breakthrough and opportunity.

Deep thanks to my buddy Bill van Erp for help with the substantial logisitics needed to actually move my system: It could not have happened otherwise. He also took most of the photos.

Actually, Radio is NOT a First Amendment Issue

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Any more than is driving a car. You need a license. Otherwise you are presumed likely to hurt people due to ignorance and lack of skill—just like Limbaugh.

The indubitable reasoning instigating the Communications Act of 1934 realized that if everyone had a radio transmitter at their will, no radio system could work. Pretty simple and extremely rational: You would have a situation where all could shout, while none listen—in other words, today’s Internet. But I digress.

As a limited national resource, the nature of the radio medium does not permit of simple analogies with the public square nor freedom of the press. You can place twenty times the newspaper vending machines in a city block than you can allocate radio stations to serve it. If you prefer, fill the sidewalk with 1000 megaphones and petitioners; but you can’t just add 1000 radio stations.

So, broadcasters are obliged to maintain their limited number of competing licenses by sharing the airwaves on behalf of the public. Necessarily, not every viewpoint will get the infinite airtime it no doubt deserves. Responsibility for the public interest is not simply heaped equally upon each station. More realistically, FCC expects good faith attempts at serving the public interest largely by encouraging a general even-handedness of representative stations in a ‘market.’ Consistent with their recently tossing “the fairness doctrine,” FCC is happier seeing competing stations than forcing each to schizophrenically adopt opposing orientations to the listener’s confusion. The relevant discussion is not at the lofty heights of the Supreme Court but at the thoroughly empirical and gritty level of how broadcasters attend to their community in context with others, and in consideration of significant variation in national market traditions.

Even the police do not have ‘free speech’ on police radios, nor pilots on aviation channels. Though the mandates for the Amateur Radio Service or Citizen’s Band are different still, the principle remains the same: Free speech takes a back seat to the prescribed communication purposes of all radio Services. And most Services maintain constant lobbying to ensure the FCC receives no cause for thought about increasing their performance standards or restricting their spectrum allocations. Thus, large-scale complaint filings such as about the SuperBowl costume fiasco have been observed to make the broadcast industry abundantly nervous. For specific stations, a large complaint file can seriously complicate their license renewal.

Today’s dysfunctional FCC has not impressed anyone with responsiveness. Nevertheless, if you want to end broadcast hate-mongering save your time arguing about free speech with dittoheads, and use it to entreat your friends to file virtually daily complaints against that lard-ass, mentally- and morally-defective, excrement-luncher—this IS the internet, after all—at:

File Complaint | FCC.gov

Jameco Re-Purposes ‘Cognitive Radio’ Article

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It was fun working with editor Frances Reed to address her diverse newsletter audience. My Story: Cognitive Radio

A comparison to the original (Cognitive Radio is Here) shows her having set a broader context, while simultaneously pulling out from me the three figures for more detail.

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Since that story there has been a further important, related development for Software-Defined Radio (SDR), which I discuss here:

Bid, Baby, Bid! Software-Defined Radio Poised To Gush!

Bid, Baby, Bid! Software-Defined Radio Poised To Gush!

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The issue of the Payroll Tax Compromise is quite beyond pretense of my understanding though I do well understand the resource largely tapped to pay for it: so-called “white space,” that is, unused frequencies in the over-allocatted TV spectrum.

I have before praised Rep. Greg Walden as an active critic of the FCC and Chairman Genachowski—that agency having been lost in the woods on issues of white space and Emergency Interoperability (among very many others). Walden has investigated the FCC and recently offered reforming legislation. But now, as House co-sponsor of the Payroll Tax bill Walden has in one stroke solved two key issues the FCC has fumbled for a decade, and deserves hearty congratulations therefore.

Walden Statement on Job Creating Spectrum Provision in Payroll Tax Conference Report – YouTube

Having spoken with Walden’s well-qualified Communications staff, I am confident they deserve specific credit for the emergency interoperability provisions, and am encouraged that they may re-visit the dubious P25 technology, hopefully leapfrogging it. (And as a cherry on top, in-filling the TV spectrum uses wavelengths that are far less controversial as unhealthy.)

You are rightly picturing many of the required new jobs building infrastructure: laying fiber, building servers and transceivers. But you might not yet realize that in truth none of this will happen without inventors and investors deploying legions of radio engineers to realize the required entirely new architectures for software-defined radios (SDR) that are agile enough to exploit the new spectrum. The challenge and opportunity for SDR is now, precisely as we are graduating programmers newly familiarized with these techniques!

That in this political environment Congress reached this compromise is certainly significant. Walden is right: It is now up to technologists to respond to the government’s lead, sharpening their management and engineering drills to ensure that electronic commerce continues to cause bandwidth to gain value against crude oil.

SJL Arrests Another Cell Phone Shield Hoax

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You are not going to get any names because I promised my counterpart confidentiality.

Over the holidays I noticed in an otherwise reputable catalog one of those $30-dollar cell phone add-ons promising to protect you from virtually all radiation. I jumped on it. The marketing manager proved to be extremely reasonable and open to discussion. He even offered to send me one to examine. I declined, because it was pointless in the absence of the claims documentation. (And I could pretty much predict what I would find—a small coil or capacitor, maybe a tiny IC.) How do you test a featureless hoax?

Of course, that the device’s claims could not actually be substantiated made my job easy enough, but specifically upon learning the following, the gentleman without hesitation removed the item from this year’s catalog, with my deep thanks and appreciation.

  • If you check the fine print that comes with the phone, it recommends non-use as the best alternative.
  • Besides that, the best safety is a wired headset because it moves the transmitter away from particularly your head. (On the argument that the wires still carry radiation, acoustic headsets are available, but a bit arcane for general use.)
  • Bluetooth comes in a very weak second because it permanently mounts a transmitter on your skull.
  • Even if you protect yourself via any of the above measures, you are still exposed to ubiquitous towers and everybody else’s phone (and wi-fi), so how can that little button possibly protect you in a real environment?
  • The cell system is actually already set up for minimum exposure because they want you to have maximum battery life.
  • The system controls the power each phone sends, according to the conditions: if you have line-of-sight to a tower, your transmission power will be low. But if you are in marginal conditions, much farther away, or particularly, within a car, the system must crank up the power from your phone—and into you.
  • Therefore, adding anything to the phone at best blocks its multi-band antennae and at worst detunes them, in either case counter-productively driving more power into your head.
  • Finally, depending on the provider, cell systems typically operate by millisecond-rate switching over a range of two-dozen different channels. And, in multiple bands from 800 to 2100 MHz. This makes talk of somehow simplistically counter-resonating ‘cell phone radiation’—falsely reifying into a simple sound bite what is in fact an extremely dynamic and complicated process—well, simply ridiculous.

Now of course, SJL has worked intensely developing technology that formerly made the same claims. But we have not made them. If there is such an effect, it is totally unproven. And there is no solution involving linear thinking: shielding with the phone won’t help (which is what your car does). You aren’t going to talk many people into wearing protective tower-climbing or lineman suits, nor metal-screened wetsuits with grounding straps. The only way to theoretically cancel an electromagnetic wave is to generate one of equal frequency and opposite phase exactly in line with its approach. Practically, under controlled conditions with a few signals this is quite difficult, and under uncontrolled real-world conditions, impossible. Considering the variety of signals with which you are bombarded as you move around (literally, thousands), do you think a deftly-priced sleek $30 plastic puck contains the required light-speed supercomputer?

The science and the evidence just isn’t there, and I was extremely glad to earn agreement on this point to the benefit of both the seller and their loyal customer base.

The only authentic antidote of which I know is correct information, starting with Cross Currents by Dr. Robert O. Becker. For an introduction to the realpolitik and regulatory issues I recommend Cell Towers by Blake Levitt.

Finally, I’m obliged to remind everyone that SJL has a patent pending through which it is hoped the technology can be developed to address this very serious issue non-linearly:

StanleyJungleib’s Channel – YouTube

Collins 30L-1 Fan Modification

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The motor is old, the blades a bit out of whack, and most of the noise is really coupled to the cabinet by the decayed and ineffective rubber isolation bushings on the three-point mounting plate.

In this parsimonious approach the two rear support plate studs are coaxed slightly to fit a 60 x 60 mm 10 CFM Fulltech unit {Jameco 213867}, while on the other side the fan’s ground hole is supported by a brass strap that needs no fastening. Though not mechanically isolated, the substitute method is inherently quiet and efficient.

And if you are motivated to search for the parts, nothing prevents you from replacing the original fan and suitable gaskets for the original mounting plate.

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Cognitive Radio is Here

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The American Radio Relay League (ARRL)—the mothership for U.S. ham radio—just reported an FCC action which should interest all observers of wireless policy. Medical devices have become miniaturized to the point where they can communicate within the body. As this is indubitably noble work, they have been authorized to use certain radio frequencies. What is initially surprising is that while we would traditionally expect these devices to be given an exclusive, protected spectrum, instead they must share it with other radio services. The full story [please follow the link below] contains important details and implications for all radio operations.

http://www.arrl.org/news/fcc-grants-secondary-service-allocation-to-wireless-broadband-medical-micropower-networks

Reviewing the article for the non-ham, FCC’s main job is to prevent radio interference. It divides different radio uses into “Services.” When a Service has a secondary allocation, in most cases its receivers must tolerate and defer to signals from the primary Service, and to the extent it creates any disruption there, a secondary must cease transmission. The ARRL was concerned not just to defend its own secondary spectrum, but humanitarianly and justifiably concerned that classifying medical devices as secondary, where they might be legally exposed to significant power from primary or other secondary Services such as ham radios could be dangerous. FCC’s response was politically bold, technically profound, and its significance can not be overlooked.

The first hint comes with mention of ‘spectrum-agile radios,’ and the other shoe drops with Genachowski’s saying: “MMNs [Medical Micropower Networks] have been shown to reliably operate in spectrum shared with other services and are a model for making more efficient use of radio spectrum by using advanced technologies such as monitoring the quality of the radio link, switching frequency bands, notching out of interfering signals and error correction coding.”

I must admit, FCC seems to have caught me off-guard here by doing something extraordinarily progressive. The technology under discussion is in fact called Cognitive Radio because the radios are smart. Their design departs from the traditional hardware model; more resembling a cell phone whose features change with the application. Cognitive radios go even farther though, essentially containing knowledge of their operational purpose, context and applicable regulations (which can vary radically internationally), in addition to wide sensitivity to their electromagnetic and physical environment.

In a broader sense, Cognitive Radio is extremely important to the future of communications because it seems to be the only strategy by which regulators can quickly respond to the dynamic needs of this wireless world, as well as to be able to efficiently allocate the spectrum available for maximum advantage. Politically, Cognitive Radio stands the 1934 Communications Act paradigm on its head: instead of blocks of spectrum and disparate radios built specifically for them, we’ll have one general-purpose radio constantly redefined in real-time with its privileges and limits according to the needs of higher-priority Services. The six or ten radios per person we now have—cell phones, Wi-fi, remote controls, security systems, garage-door openers, Family, General Mobile or Citizen’s Band—are in principle replaced by one device that implements whatever radio function is needed as it is needed through software. And to preserve its battery and respect other radios it will only emit the minimum radiation required to do its job.

While to the experienced ham the concept of a Cognitive radio that might offer different features depending on when and where you are may be unsettling, in ten years it could also well be the only feasible solution to the problem of constantly increasing spectrum demand. One can also look at this evolution as reinventing and distributing for each user our beloved and forgotten, problem-solving FCC Field Engineers, albeit robotically. But, challenging questions will arise. For example, what happens to short-wave listening (SWL) and radio distance (DX) operating skills if the radios are regulated to use the most reliable routes at the least power? And when all radios (that is, phones) have adaptive emergency response capability will the traditional social justification for Amateur Radio even remain or be allowed? Finally, while dynamically inter-filling the spectrum may give more users better service through fewer, lower-power transmitters, the technique can potentially raise the population’s aggregate daily radiation exposure as it is adopted by more Services.

ARRL appropriately emphasizes that much more experimentation remains to ensure the safety of MMNs under secondary status. Both the developers and the FCC seem willing to address those challenges. And no, I don’t think my Aug 19 demand had anything to do with it. Innovative programs like this require smart people rendering considerable sustained interdisciplinary effort. That they are now willing to subject their concept to the acid-test of intimately serving life itself speaks enormously of both their commitment to an urgent new vision for radio in general, and the performance promised by Cognitive Radio specifically. I wish the entire effort good luck. Its success will profoundly affect and advance radio communications policy for the rest of the century.

Heathkit HP-23 Capacitors

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Guess what, capacitors of the same era as the Collins 30L-1 showing exactly the same signs of failure, and what replacement looks like.

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